组织工程复合物进行兔尿流改道

Tissue-engineered graft for urinary diversion in rabbits

背景：根治性膀胱切除是目前对于肌层浸润性膀胱癌最有效的治疗手段，膀胱切除后尿流改道需利用肠道，并发症较多。目的：试用膀胱脱细胞基质和尿路上皮细胞构建组织工程化卷管进行尿流改道。 方法：制作兔脱细胞基质，体外培养扩增兔膀胱上皮细胞，将上皮细胞种植到兔脱细胞基质上，培养7 d后制作成4 cm长的卷管；新西兰兔28只，其中实验组24只，分6组每组4只，分别行保留膀胱三角区的膀胱大部分切除，再将膀胱三角区与组织工程化卷管吻合，网膜包裹卷管；对照组4只，利用未种植细胞的脱细胞基质制作成流出道并与膀胱三角区吻合。分别于手术后1，2，4，8周取标本做苏木精-伊红染色，8周后对复合物进行免疫组织化学检测。结果与结论：实验组所有的动物均存活，苏木精-伊红染色显示流出道覆盖上皮，随着时间的推移，种植的上皮细胞与脱细胞基质逐渐融合，8周后免疫组织化学可见抗细胞角蛋白单克隆抗体 AE1/AE3阳性，抗ZO-1抗体阳性，证实流出道组织内有成熟上皮细胞覆盖,尿路上皮细胞之间有连接功能；对照组4只兔术后2周内均死亡，尸体解剖见流出道瘢痕形成，闭锁，双肾重度积水。结果表明，利用种植有尿路上皮细胞的脱细胞基质制作成组织工程化卷管在动物体内进行尿流改道是可行的，流出道内腔有成熟上皮覆盖，具有防止尿外渗的功能。

BACKGROUND： For muscle invasive bladder cancer, radical cystectomy is the most effective treatment now and urinary diversion is often necessary. The use of intestinal tissue for urinary diversion is frequently associated with complications.OBJECTIVE： To study the feasibility of tissue-engineered graft using bladder epithelial cells and bladder acellular matrix （BAM） for urinary diversion in rabbits.METHODS： BAM of rabbits was made in vitro. Bladder epithelial cells of rabbits were cultivated and expanded in vitro, then implanted into the BAM and cultured for 7 days before making a 4 cm conduit. In the experimental group, 24 New Zealand rabbits, divided into six groups with four in each, were subjected to excising most of the bladder with bladder trigone retained. Then the retained bladder trigone were anatomized with the conduit which was then wrapped by omentum. In the control group, the conduit was made using unseeded BAM and anatomized with the retained bladder trigone in the four New Zealand rabbits. Specimens of tissue-engineered grafts were obtained at 1, 2, 4, and 8 weeks after surgery respectively and were stained with haematoxylin and eosin. Immunohistochemistry examination was done at 8 weeks postoperatively.RESULTS AND CONCLUSION： All animals were alive in the experimental group. Hematoxylin and eosin staining showed epithelial coverage on the lumen of tissue-engineered conduit. With the time going on, grown epithelial cells gradually integrated with the BAM. Immunohistochemistry showed anti-cytokeratin AE1/AE3 antibody and anti-ZO1 antibody were positive, confirming that there were mature and functional epithelial cells on the lumen of conduit. In the control group, four rabbits were all dead within 2 weeks. Scar formation, atresia, and severe hydronephrosis were found in the process of autopsy. It is feasible to prepare tissue-engineered grafts using bladder epithelial cells and BAM for urinary diversion in rabbits.